I've done quite a few tied T-shirt quilts. No matter what the batting says, I tied every 3" in the blocks. I made a little felt square to easily space my ties. Ties on the imprints don't look funny and don't distract. One thing to keep in mind, T-shirt quilts combined with an all cotton batting like W&N are heavy especially when wet (during laundering). You are better off putting more ties in than less because the stress on the seams and the material itself is quite demanding when the quilt is wet. More ties will help distribute that stress and keep seams from popping and t-shirts from tearing at the ties.